Three-dimensional absorbing Markov chain model for video streaming over IEEE 802.11 wireless networks

The varying wireless channel conditions necessitate the use of error control mechanisms for reliable transmission of video streaming applications. Forward error correction (FEC) and automatic repeat request (ARQ) mechanisms are used at the data-link layer of IEEE 802.11 based wireless networks to avoid and recover from the channel errors. In this paper, a three-dimensional absorbing Markov chain model is presented to accurately calculate the packet transmission time when both the FEC and ARQ mechanisms are used. Based on the calculated packet transmission time and given maximum number of transmission attempts, the number of redundant FEC packets is adjusted to achieve an optimum tradeoff between network overhead and delay. Numerical results show that the three-dimensional absorbing Markov chain model accurately captures the packet delivery dynamics for a given maximum number of transmission attempts at the data-link layer. With the knowledge of accurate packet transmission time, the FEC parameter is adjusted to achieve higher quality video at the terminal devices. The adjustment of the number of FEC packets based on the proposed three-dimensional model brings the combined advantages of reduced network overhead and enhanced video quality.